[gmx-users] Virial

[Yuguang Mu]

Daer All,

I found that the virial calculation of my system have quite different
results compared with single and double precision codes.
I attach 3 figures show the Vir-xx , Vir-xy, and Vir-xz.
The red line is from double precision calculations.
It clear shows that the diaganal parts are similar , but the off diagonal
parts are quite different !

In the double precision case, nearly all the off diagonal Vir are zero.
It should be , right ? Because I use orthogonal box.

So what' wrong with the single precision calculations of Vir ?

The final results are that after pressure equilibrium, I got different box
size (box, x, y,z are different) , and it turns out that the results from
single precision calculations are not reasonable.



Dr. Yuguang Mu
Institute for Physical and Theoretical Chemistry
J.W. Goethe University Frankfurt am Main
Marie Curie Str. 11
60439 Frankfurt/Main, Germany
Tel: +49-(0)69-798-29711

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